Drivers are transducers which convert electricity to various ranges of sound frequencies. It has been known for many years to provide speakers having a plurality of drivers generating sounds of varying audible frequencies. Such speakers are sometimes referred to as multiway loudspeakers. Drivers include a diaphragm that moves back and forth to create pressure waves in a column of air in front of the driver, and depending on the application, at some angle to the sides. The diaphragm is typically in the shape of a cone and has a diameter. The use of multiple drivers is done in an effort to enhance sound quality. The combinations typically take on the form of woofers (or sub-woofers) for emitting sounds in a low frequency range, midrange drivers for emitting sound in a middle range, and tweeters for emitting sounds in a high frequency range. Breaking up a sound signal in this manner has been found to advantageously cover the range of sounds a human can hear. The multiple drivers may be mounted coaxially normal to a floor or ground. Such speakers are known as omindirectional speakers, and they provide a sound field which allows a person positioned in any direction around the speaker to hear the wide bandwidth (frequency range) sound produced by the speaker.
A wide variety of speaker designs have been created in an effort to enhance sound quality. For example, known speaker designs include U.S. Pat. No. 5,115,882 to Woody. Woody discloses a speaker comprising a pair of drivers, one tweeter and one midrange, with each driver aligned in the same direction. Each driver is also provided with a conical shaped dispersion surfaces. However, irregular surfaces, such as the tip of the conical shaped dispersion surface, have been found to introduce distortions in sound quality. Such conical shaped waveguides have proved to be less than ideal. In general, irregular surfaces produce reflections in sound waves which are out of phase with other sound waves generated by the speaker, and can also result in reinforcement of some frequencies and cancellation of others.
U.S. Pat. No. 4,182,931 to Kenner discloses a pair of drivers which are coaxial and face each other, and each driver is provided with a dome (waveguide). However, the diameter of the domes/waveguides is less than the diameter of the drivers, and the domes/waveguides have a flat reflecting surface. This has the effect of introducing distortions in sound quality. Another known speaker design has a coaxial tweeter, a trapezoidal midrange driver and subwoofer. A waveguide is positioned above the tweeter, and another generally spherical shaped waveguide is positioned between the tweeter and the midrange driver. However, the spherically shaped waveguide is smaller than the midrange driver, again resulting in some distortions in the sound quality. An idealized omindirectional speaker would reproduce sound at a point, and the sound would radiate outward from the point all directions. Sound waves diverging would be free of interferences. It would be desirable to provide an omnidirectional speaker with a plurality of drivers which provides enhanced sound quality, which reduces background noises and distortions, and which is therefore more faithful to an original recording.